In addition to two bullets found embedded in Pentagon office windows, four other bullets struck the building Tuesday morning, according to the Pentagon Force Protection Agency.
"It has been determined that at least six shots were fired," read a statement from PFPA Director Steven Calvery. "As previously stated, two exterior windows were impacted by bullets. Upon investigation, it has been determined that four other bullets hit the Pentagon's façade."
Evidence from the scene is at an FBI lab, and investigators are reviewing surveillance videos from the Pentagon, nearby buildings and roads in the area.
According to the Pentagon, at least six shots were fired at about 4:55 a.m. Tuesday. Pentagon police and construction workers heard a series of shots fired in or near the south parking area of the Pentagon, prompting Pentagon Police to lock down the reservation. Nothing was found and the Pentagon reopened at about 5:40 a.m.
A second sweep, with assistance from Arlington police and K-9 units, also turned up nothing, but at about 6:20 a.m., someone noticed damaged office windows on the third and fourth floors on the side of the Pentagon that faces I-395. Fragments from two bullets were embedded in the windows. The bullets had shattered but not penetrated the windows. Authorities believe they were fired from a high-powered rifle or rifles. Virginia State Police shut down part of I-395 to assist a Pentagon Police search for evidence.
Security has been tightened at the Pentagon and other federal landmarks and buildings in the D.C. area.
Over the weekend, several rounds were fired at the National Museum of the Marine Corps and Heritage Center in Triangle, Va., about 30 miles south of the Pentagon. It's unknown if the incidents are connected, but the bullets from that shooting have been sent to the FBI.
On the evening of March 4, 36-year-old John Patrick Bedell, of Hollister, Calif., exchanged gunfire with two PFPA officers at a pre-screening checkpoint at the Pentagon Metro Station, authorities said. The officers were wounded but stopped Bedell, who later died at a local hospital. That shooting led to security improvements.
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